1. Field of the Invention
Embodiments of the present invention generally relate to testing of partially or fully completed semiconductor devices and, more particularly, to stiffener assemblies for use in connection with apparatus for testing such devices.
2. Description of the Related Art
When testing partially or fully completed semiconductor devices formed on a semiconductor substrate, such as integrated circuits and the like, a plurality of contact elements are typically brought into contact with the device to be tested—sometimes referred to as a device under test (or DUT). The contact elements are typically part of a probe card assembly or other similar device coupled to a test mechanism that provides electrical signals to terminals on the DUT in accordance with a predetermined testing protocol.
In order to sufficiently and accurately contact all desired terminals of the DUT during a particular testing protocol, the contact elements disposed on the probe card assembly must be brought into contact with the terminals of the DUT and must maintain alignment therewith. However, various forces applied to the probe card assembly may cause the assembly to deflect in a manner that may cause misalignment of the contact elements. Accordingly, the probe card assembly generally includes stiffening members and/or assemblies designed to minimize such deflection of the probe card assembly.
Generally, such stiffening members or assemblies have relatively large masses to suitably provide the stiffening benefit required during testing. However, such testing often occurs at high temperatures, for example up to about 150 degrees Celsius, thereby requiring increased time for the probe card assembly to reach a steady state suitable to begin testing of the DUT. However, such delays in testing while waiting for the probe card assembly to heat up is costly and reduces availability of the equipment for testing. Moreover, the large mass of the stiffening members or assemblies further exacerbates this problem.
Therefore, there is a need for an improved stiffening element for use in the probe card assembly.